Water heater



H. J. LONG WATER HEATER Oct. 29, 1935.

Filed Sept. 29, 1934 INVENTOR Herberfi 7.10 7

QidQw ATTORN EY Patented Oct. 29, 1935 UNITED=STATES PATENT OFFICE WATER HEATER Herbert J. Long, Springfield, Mass" assignor to United American Bosch Corporation, Springfield, Mass., a corporation of New York Application September 29, 1934, Serial No. 746,168

5 Claims.

This invention relates to water heaters and particularly to that type in which an automatic gas or other burner is utilized for the purpose of maintaining a domestic hot water supply.

Among the objects of this invention is the provision of a water heater which is very compact, and which may therefore be installed in present systems of range and furnace heaters where available space is limited.

Heretofore in water heaters the major portion of the radiated heat from the flame of the burner was lost, inasmuch as the heating surface was placed over the burner and the heat radiated sideways was lost to the surrounding jacket. Even though the jacket is thoroughly insulated,

'the heat so radiated does not assist materially in a heating the water since the jacket is not in good.

conducting relation to the heating element.

It is one of the objects of this invention to conserve the heat normally lost in radiation. To this end it is a feature of this invention to provide a construction in which the wall of the combustion chamber is integral with fins of the heating element, whereby any heat absorbed by the combustion chamber wall is directly conducted through the fins into the water thus adding to the efficiency of the heater.

A further important defect in connection with water heaters as heretofore constructed resides in the fact that either the flame or the hot gaseous products of combustion from the burner are permitted to impinge directly uponcold surfaces of the boiler or heating coils. If the process of combustion has not been completed at the time of such impingement; the same is interrupted r esulting in inefficient combustion and in deposits of carbon and condensate. To avoid these difliculties, the burnerhas frequently been placed some distance below the boiler or heating coils to insure complete combustion of the fuelprior to contact of the products of combustion with the cold surfaces of such boiler or coils. constructions, due to the distance between the burner and the surface intended to be heated, a considerable amount of heat is lost, and further- In such more vapors resulting from the combustion tend to condense upon the cold surfaces causing further heat loss. Also the corrosive nature'of the condensate damages parts of the heater giving it a short life.

Another object of this invention isto eliminate ineflicient combustion, carbon deposits and other disadvantages normally resulting from placing the burner close to the boiler or heating coils, and at the same time to avoid the heat losses resulting burner is disposed immediately adjacent the .16

j upper end of the inner tubular portion l3 pro- The fins II extend longitudinally of the inner which chamber the burner l5 projects. It will be noted that the jets IQ of the burner l5 open into from placing the burner far below the heating element. Condensation present in both of these prior types is avoided also. 7

To this end I provide a heating element in which the fin surface is great in proportion to 5 the water surface. The fin surface is therefore maintained at a temperature sufliciently high to avoid any tendency to quench the flame or otherwise interfere with the combustion process. The

heating element, combustion occurring adjacent the finned surfaces. The construction is such that the burning gases are surrounded upon all sides by closely spaced'heat conducting surfaces practically none of which surfaces'has an oppo- 15 site side forming a water surface.

These and other objects and features of thisinvention will be apparent to those skilled iu'the art from the following description taken in conjunction with the accompanying drawing, in go which Fig. 1 is a vertical sectional view of a heater constructed in accordance with this invention, parts being shown in side elevation; and Fig. 2 is a top plan of the heating element thereof. 25

In the drawing reference numeral l0 indicates a heating element which is formed of a single casting of bronze or other suitable metal. This casting consists of an outer tubular portion ll having radial fins l2 extending inwardly therefrom and joined at the inner ends by an inner tubular portion l3 forming a water chamber. The

jects slightly above the upper end of the outer tubular portion and its lower end terminate somewhat above the lower end of said outer portion member throughout that portion of its length which lies within the outer cylindrical portion.

A'small circular chamber ll remains below the 0 central tubular member l3 and the fins ll into the chamber H at a point which is slightly above the lower edge of the outer tubular portion ll. 45-

The flame from the burner is therefore entirely surrounded by this outer member. Heat radiated outwardly from the burning gas is absorbed by the outer member and thence is conducted through the fins to the central water chamber. 50

Part ofthe combustion occurs in the chamber l4 but the greater part occurs in the tubular spaces between the fins II. The jets l6 are so disposed as to supply equal heat to each of the spaces between the fins.

The heat absorbing surfaces to which the buming gases are exposed, are sufficiently close together to efliciently extract the heat thereof. It will also be observed that only at a single point in circumference of each of these spaces between the fins are the gases exposed to a wall which is directly cooled by water upon its opposite surface, and even this point will be maintained at a relatively high temperature because the area of the heat absorbing "surface which is directly connected thereto is large in proportion to the water surface. The burning gases are not chilled before the combustion process is complete as is v the case where the same'impinge against a cold surface but rather combustion is'maintained and aided by the hot metal.

v ance I9 to avoid loss of heat from the element to the metallic portion of the jacket. An outer jacket 20 is spaced from the heating element I 0 ,and between theseis packed a suitable insulating material such as mineral wool 22. The outer jacket 20' extends upwardly beyond the heating element l0 and an inner jacket 2| centered on the upper end of said element and spaced from the outer jacket provides an insulating space which may also be packed with'mineral wool.

A water tube 23 connects with the projecting end of the inner tubular portion l3 of the heating element and. conducts the'water upwardly therefrom in heat absorbing relationto the gases in the upper portion of the heater. In this portion it will be observed that the heat absorbing surface which consists merely of the outer surface of the tube 23 is not large in proportion to the .water surface formed by the inside of the tube.

.cHowever, by the time the gases reach this portion of-the heater combustion has been completed so that the same canno longer be interfered with. Also the water within the tube l3 will normally be warm so there is no opportunity for condensation of vapors present in the combustion products.

The water tube 23 is connected at its upper end to an outlet member 24. A flange 25 is provided integral with member 24 spaced from the upper end of the heater jacket to provide a connection for a' discharge conduit to permit the egress of gases. A portion of flange 25 extends downwardly as at 25', preventing foreign matter from falling into'the heater. Hot water discharge connections are provided at 26.

A thermostat 21 is mounted upon the outlet member, the control element 28 of which extends downwardly through tube 23 into the waterchamber of the heating element, and carries at its upper end a gas control valve 29.

While there is herein described but a single form of my invention, other forms and modifications within the scope of the appended claims will be apparent to those skilled in the art.

Havingthus described the invention, what is claimed as new'is:

1. In a water heating element formed of a central tube having fins projecting radially therefrom and extending longitudinally thereof, an outer cylindrical member integral with the outer ends of said fins, the outer cylindrical member projecting beyond the inner tubular member at one end thereof, and a burner having jets within said projecting portion of said outer cylindrical member.

2. A water heater comprising a vertically extending jacket member having a lower cylindrical portion and a frustro-conical portion superimposed thereon, a cylindrical heating element including an inner tubular water chamber extending centrally therethrough and connected integrally therewith within said cylindrical portion of said jacket-and spaced therefrom to provide an insulating space therebetween, a burner having jets projecting into the lower portion of said heating element.

3. In a water heater, a vertically extending external jacket having a lower cylindrical portion and an upper frustro-conical portion, a cylindricalheating element including an inner tubularwater chamber extending centrally therethrough and connected integrally therewith within the lower cylindrical portion of said" outer jacket,-

spaced therefrom to provide a space for insulating material therebetween, an inner jacket member within the frustro-conical portion of said outer jacket, said inner member resting upon and coaxial with said cylindrical heating element and providing with said external jacket a space for insulating material.

4. 'A heating element formed of a single casting comprising a central water tube having fins projecting radially therefrom and extending longitudinally thereof, and an outer cylindrical member connecting the outer ends of said fins.

5. Ina water heater, a casing, a heating element extending longitudinally thereof, said heat ing element comprising a central water tube having fins integral therewith and extending longitudinally thereof, a gas burner positioned below said heating element, a valve above said HERBERT J. LONG. 

